The Battle of Cos is fought ca 258 BCE between an Antigonid fleet and a Ptolemaic fleet.

Antigonus II Gonatas leads his forces to victory over Patroclus, admiral of Ptolemy II.

It has been widely assumed that the battle severely damaged Ptolemaic control of the Aegean.

After the battle, Antigonus dedicateshis flagship to Apollo.The date of the battle is uncertain, although it must fall within the period 262-256 BCE.

Hammond dates it as late as 255 BCE.It is possible that this is the victory which the Nike, or Winged Victory of Samothrace, commemorates.